This invention relates to a roofing products and structures and method and, more particularly, to roofing products for pitched roofs which are constituted by integrally molded or formed fins, vanes or blades which provide shading and air circulation, air space for heat insulation and debris impact absorbing functions.
In the prior art, asphalt, asbestos, or wood shingles, clay tile, slate, etc. have been used in roof construction wherein after the usually 4.times.8 (plywood or particle-board) sheets have been installed, an impregnated paper is rolled upon the roofing base and then shingles of various constructions are layered directly upon this construction. When the shingles are asbestos, asphalt and the like reflective marble chips, and similar materials have been adhered to the surface of the roofing product, to keep the roof cool, it is still quite common for the interior structure to become extremely hot because of the absorption and transmission of radiant or solar energy from the sun. Cooler clay and slate roofing materials are heavy and require substantially sturdier roof foundation structures to maintain them in position. In addition, when these clay and slate roofs are damaged, repair of them is costly and difficult.
The object of the present invention is to provide improved roofing products which can be easily and quickly installed, which provide both air circulation, thermal insulation and impact energy absorption at relatively low cost.
According to the invention, roofing, whether in shingle form or in roll form is provided for pitched roofs which is constituted by integrally molded or formed blades, vanes, fins and the like and a flat attachment or securement member or panel. These blades provide shade to the roof, convert radiant energy to thermal energy at a distance from the attachment as securement member and air circulation in the spaces between the blade, vanes or fins to sluff-off thermal energy, as well as providing shading for the next lower fin by virtue of the overhang of fins immediately thereabove. Since the blades, vanes or fins are thin elements, heat transfer to the roof is greatly attenuated. Moreover, the fins, blades forming the vented roofing structure absorb impact of falling limbs, stones, hail and the like. In a preferred embodiment, a base attachment structure or securement member for laying flat on the roof support foundation structure is provided with one or more outwardly extending fins or blades which, depending on the pitch of the roofing, provides a high degree of shading for the underlying structure and, a high degree of air circulation between blades or fins.
In addition, the blades, vanes or fins may have ribbed surfaces which makes them more conducive to sluffing off heat. These heat sluffing ribs may be on the top, bottom or both surfaces. This form of self-shading roof construction may have the fins or vanes or blades manufactured as curved with deformed, notched or peripherally modified leading edges so as to allow for the ventilation or air to circulate and also to draw off heat build-up. While in one preferred embodiment, the blades are horizontal relative to the roof, in effect, the roofing provides a multiple roof configuration which shades, ventilates and protects each other and, in another preferred embodiment, the vanes, blades or fins are vertical, in other embodiments, the blades, vanes or fins could be at other angles.
Roofing structure according to the invention allow and promote (through convection) circulating air around and between the roof to absorb heat and carry it away (just as air passing through an automobile radiator). In some embodiments, pockets of air are sealed to form insulated low heat transfer spaces below the roofing per se.
The roofing can be implemented in conventional shingle sizing or roll roofing form and manufactured by casting, extrusion, folding from sheet stock, rubber and plastics (such as PVC, white PVC is presently being utilized in sheet formatted flat roofing for industrial buildings HYPALON.TM.) and smooth or rough surface textured, tapered or straight blades or vanes. As noted above, all of the embodiments protect not only from solar energy (heat) but from impacts such as hail and falling limbs. Furthermore, any snow or ice built-up on the outer layers is insulated from the base layers by the intervening air spaces and pockets. Even wind forces, depending on their angle of attack (e.g., the vector angle) will, in summer, cool both vane surfaces and, in winter, be prevented from heat extracting air flows over the roof by trapped elongated pockets of air and any small minute fluttering of the vanes or blades in winds will tend to prevent ice build-up, particularly in the milder or temperate climates.
In the preferred embodiment, the roofing is provided with integral tabs for attaching the roofing to the roof sub-base structure. In one embodiment, an alignment ridge is formed on the selvage or underlap edge of the roofing which may be provided with one or more nailing grooves or nail locating grooves. An alignment rib or tongue and coacting alignment groove snap together to securely integrate the roofing by interlocking of the ranks of individual products to each other. A roof peak element has two sides, one for each roof side and is flexible to accommodate varying roof pitches.
In still another embodiment, the vanes, fins or blades are in the form of T-shaped or curved ribs, there being alternate tall and short T-shaped or curved ribs with their overlapping blades formed in an extrusion with edges that interfit and interlock with adjoining ranks or tiers of roofing members so that the roofing can be installed more rapidly working from one edge of the roofing (say the left edge to the opposite edge, say the right edge) and function as an integrated roof.